obviously i know it will put the emmisions up but roughly by how much? had my golf VR6 with a de-cat on the probe the other day and it was 0.75 on the co emmisions (fail), hydrocarbons was green as was lambda probe emmisions.

 

 

0.75 is not really sky-high when you bear in mind that old carburetted non-cat cars and bikes may have up to 4.5% CO.

So basically 0.75 sounds about right for a modern fuel injected car with the catalytic converter missing.

 

does effect some cars more than others as loads of FRS models just breeze through with de-cats

 

It's also an mot failure now not to have a cat fitted

 

Completely depends on the car, as to what effect it will have.

Some modern engines now, chuck a load of fuel in on start up, to help ignite the cat and get it working (hot) quicker etc

 

its a golf vr6 mate

 

Iam sure that now even if your car passes its emissions but hasn't got a cat it will fail. Same as if your management light is on but it passes emissions it's a fail